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This paper analyzes the value of highway travel time information systems. This is achieved by using notions of expected utility theory to develop a departure time selection and route choice model. The model assumes that every driver has a level of accepted lateness for his trip and some perceived knowledge of the travel times on the route. Only these two inputs support his decisions. The results of the model are used to compute the unreliability costs of the trip (i.e. scheduling costs and stress) and to obtain the benefits of real-time information systems. Results show that travel time information only has a significant value when there is an important scheduled activity at destination (e.g. morning commute trips), in case of total uncertainty about the conditions of the trip (e.g. sporadic trips), or when more than one route is possible. Systems with very high accuracy are not in better terms. The paper also highlights that the value of the information may not benefit only the user, but all drivers, even those without information. This social benefit of information reduces the marginal benefit of being informed (i.e. the user benefit). While this reduction of the social costs can be a policy objective, there is no reason to expect individuals to pay out-of-pocket for travel time information, beyond the user value. [ABSTRACT FROM AUTHOR]

This paper presents the Dynamic Speed Limit (DSL) experiment that took place in June 2013 on the last 13 km stretch of B-23 freeway accessing Barcelona. The DSL system installed on that freeway in addition to the high density of surveillance equipment available makes this stretch a suitable highway tab. The objective of the experiment was to construct a comprehensive database when different speed limits apply. Detailed measurements of speed, vehicle count, occupancy, lane changing activity and travel time were taken. These simultaneous measurements obtained from very different types of monitoring equipment have been grouped into a single database. This comprehensive DSL database, unique in its nature, is made publicly available to the whole research community. The paper describes in detail the experiment and presents some preliminary results. [ABSTRACT FROM AUTHOR]

The boom and impact of the autonomous and connected vehicle in recent years is being remarkable. However, its development is subject to overcoming a broad set of challenges. Specifically, this paper will discuss the aspects most related to the technology involved. The difficulties for an adequate perception of the environment or how to adopt correct and robust decisions are analyzed. The requirements on communications and infrastructure are also addressed. In the same way, the human factor cannot be ignored. These challenges have led to some actions, in many cases at a multi-sectorial and international level, both at the level of research and real implementation. Finally, there is a forecast of the foreseeable effects on the mobility model. [ABSTRACT FROM AUTHOR]

Vehicle deceleration problem should have a precise resolution, because any failure in the physical process of this phenomenon can cause several types of traffic accidents. The main braking mechanisms are: friction braking, with high deceleration ratio, and engine braking, with less deceleration ratio, but more stable and important to assist the former, especially in roads affected by snow or ice or with winding geometry. In this paper an analysis of engine braking action and forces that oppose to vehicle advance and contribute to braking (gravity in uphill situation, rolling and aerodynamic resistance) is presented, without considering yet, the friction brake mathematical model. The main project objective is the design of a car driving simulator for use in verifying the geometric consistency of roads in various conditions of use. [ABSTRACT FROM AUTHOR]

Among winter period, the climatic conditions in the state of Lleida, where L4 sector is located, cause an important number of days with northern or north-western wind which maintains a very low temperatures with a dry road. Our experience allows estimate that the permanence of the salt on the road is higher in dry than in wet road conditions, especially when we use brine for anti-icing treatments. But, the consequence of a hypothetic accident, where the driver denounces ice on the road when we have not realize the pertinent treatment, promotes us to carry out anti-icing treatments to defend ourselves against possible claims and not because they were really necessary. These unnecessary treatments became an important increase of the economic cost of the infrastructure's maintenance and a higher impact on the environment. This paper expects to provide the trends about the taken salinity measurements reveal, under various conditions (e.g. traffic, different pavements types and different treatment types). Decision makers might use these trends as a tool for understanding the connection between the different factors that are involved about the amount of residual salt on the dry road. In future seasons, we could get better relationship between the residual salt and the traffic conditions. [ABSTRACT FROM AUTHOR]